spi/bfin_spi: drop bits_per_word from client data

No other SPI controller has this field, and SPI clients should be setting
this up in their own drivers.  So drop it from the Blackfin controller to
keep people from using it.
Signed-off-by: NMike Frysinger <vapier@gentoo.org>
Signed-off-by: NBob Liu <lliubbo@gmail.com>

arch/blackfin/include/asm/bfin5xx_spi.h

@@ -77,7 +77,6 @@ struct bfin5xx_spi_master {
 struct bfin5xx_spi_chip {
 	u16 ctl_reg;
 	u8 enable_dma;
-	u8 bits_per_word;
 	u16 cs_chg_udelay; /* Some devices require 16-bit delays */
 	/* Value to send if no TX value is supplied, usually 0x0 or 0xFFFF */
 	u16 idle_tx_val;